Investigation of the environmental factors associated with the inflow of Sargassum horneri into the Korean Peninsula using GOCI

<p> </p><ul><li> <p><em>Sargassum horneri</em> is one of the major components of the floating sargassum that is distributed widely along the coast, including Korea, China and Japan. <em>Sargassum horneri</em> has an air pocket called an ‘air sec’ on its body which leads to a floating life, and drifts by ocean currents and winds. Due to these characteristics, blooms of <em>Sargassum horneri</em> have occurred April-June in the East China Sea. If these blooms flow into Jeju Island in South Korea, the blooms can cause enormous damage to fishing activities and the marine tourism industry. In order to minimize the damage caused by these blooms, we have been studied using remote sensing and field measurements.</p> <p>This study investigates environmental factors associated to the inflow of <em>Sargassum horneri</em> into Korean Peninsula. We used floating algae detection algorithm developed by a Geostationary Ocean Color Imager (GOCI). Since GOCI provides data of the seas surrounding the Korea eight times a day (00 to 07 UTC), it is suitable to monitor the blooms. The algorithm was made using the Red-edge effect which has a sharply rising reflectivity at around 700 nm but a low reflectivity in the red area (660-680 nm). And it was considered that the reflectivity of background seawater which varies from place to place is eliminated. Based on the results of the algorithm for detecting floating algae, <em>Sargassum horneri</em>’s inflow into the Korean Peninsula was analyzed January to June for six years (2014 to 2019). Also, the environment factors affecting to the inflow path were investigated each months and years.</p> </li> </ul><p> </p>

Study of Organization and Dynamics of Multi-Tryptophan Protein Molecules Utilizing Red Edge Excitation Shift Approach

A shift in the fluorescence emission maxima with gradual increase in excitation wavelength is termed as red edge excitation shift (REES). Tryptophan residues are widely utilized as intrinsic fluorescence probe to investigate the protein structures. Wavelength selective tryptophan fluorescence can explore the dynamics of surrounded water molecules, the ubiquitous biological solvent. Thus REES experiment of various protein conformational states can provide significant input to the study of protein folding pathway and it can also be useful to study interaction of proteins with others. In this review article, we shall focus on red edge effect of various multi-tryptophan proteins in their respective native, intermediate and denatured state.

The solvation dynamics and rotational relaxation of protonated meso-tetrakis(4-sulfonatophenyl)porphyrin in imidazolium-based ionic liquids measured with a streak camera

For the steady-state behavior of diprotonated tetrakis(4-sulfonatophenyl)porphyrin (H4TPPS2-) in five imidazolium ionic liquids (ILs), the absorption positions of H4TPPS2- primarily depend on the constituent ions of the ILs whereas the emission positions of H4TPPS2- strongly depend on the polarity of the ILs. The fluorescence spectra of H4TPPS2- with different excitation wavelengths show no red-edge effect in our system. The dynamics of H4TPPS2- in ILs is further studied with a streak camera, and the relaxation process of ILs occurs on two different time scales. The short lived component attributed to the local motion of the cations and the anions around the porphine core varies from 32 to 196 ps. The long lived one originated from the collective diffusive motions of the cations and anions varies from 460 to 1072 ps. The average solvation time depends on the viscosity of the ILs. The rotational relaxation times of H4TPPS2- decrease as the viscosity of the ILs decreases.